Facile Synthesis of Substituted Tetracyanocyclopropanes via Cyclopropanation of Olefin with Arsonium Ylides

A facile and efficient methodology for the preparation of 3-aryl-1,1,2,2-tetracyanocyclopropanes is described. Arsonium bromides 2 reacted with benzylidenemalononitriles 1 in the presence of KF•2H2O to provide 3-aryl substituted tetracyanocyclopropanes 3 in high to excellent yields.